Mayday! TC29D won't start!

[booboo04]

OK fellas (and ladies!), really need your help. My little tractor will not start. A very experienced mechanic and I have been all over this thing for hours; make that days now. We had a bevy of issues, all of which we dealt with as we diagnosed. Starter (new) and battery (new). Glow plug timer (new) as well as one of the three relays.

ORIGINALLY: starter wouldn't turn over. Bench tested it, wouldn't pull in. Replaced starter.
Battery wouldn't hold a load. Replaced battery.

THEN: couldn't get the glow plugs to heat - no 12v to them. Replaced the ignition switch.
Also found problem with the plug that connects the ignition switch into the harness, so we bypassed that. Juice going through switch to the glow plug relay (12v). But from the relay to the glow plugs we only get 1.5 to 2v. Replace the timer relay. Still NOTHING...

Now we are really stumped. At one point, we got a click out of the third of the three like relays (which the parts diagram says is the PTO safety relay). We've swapped the relays around since they are all the same, and even carefully tried the new relay in each of the three positions. No joy. Wearing out the old wiring diagram.

ANY help, will dance at your next party!

 

[Soundguy]

As a test, bypass cutout switches. Be care full doing so.. standard precautions.. clutch in, trans neutral, don't get run over, don't start it from the ground, etc.

 

[booboo04]

Sounds great...now, where are the cutout switches? The seat switch was gone before I bought the tractor.

Thanks!

 

[Soundguy]

Since you are not familiar with this machine, I reccomed you have your pro mechanic do it, for safety issues.

 

[David Devuono]

From what I can tell, that is a hydrostatic transmission. A Diesel just needs fuel, air and to be cranked over. Since your starter issue has been fixed I would assume the tractor is turning over now but sill won't start. So you are looking at the glow plugs but then if you brought the tractor into a warm area, it should still start eventually without the glow plug. So being hydrostatic and being able to crank it, it must mean no fuel to engine. Newer tractors do not have a cable or Rod to shut the fuel and stop the engine, its done with a selenoid. You should hear that selenoid click when turn the key to start the tractor. On my Kubota, sometimes I have to play with the forward reverse pedals to get it to start.

 

[David Devuono]

So I am saying, with the key in the start position I have to rock the fwd rev pedals back and forth.

 

[George2615]

You mention getting only 1.5 to 2V from relay to glow plugs. What if the wire from the timer to plugs is unhooked and tested. If you get 12V then, one or more of the glow plugs could be shorted to ground which is pulling volts down to the 1.5-2 you read.

 

[booboo04]

When we bypassed everything (hooked the battery directly to the starter) the engine did turn over. Yes, it is a hydrostatic transmission. Also, another clue: no glow plug light on the dash.

Are these safety switches next to and over the left rear tire?

I don't know how much more intimately I can know this tractor, Soundguy!

Thanks!

 

[MikePA]

The 'D' in all TCxxD tractors mean Deluxe which means hydrostatic transmission.

When I start mine, trans has to be in Neutral and Clutch depressed. Every now and then, I have to wiggle the transmission lever to make sure it's in Neutral. If in doubt, I move it to the other Neutral position. More than one person on TBN has found the problem to be connections under the fender have been pulled apart.

 

[PILOON]

Being very careful, using a jumper directly from the battery plus to the common glow plug interconnect, hold it there for about 10-15 seconds and then attempt a start.
Glow plugs are nothing but resisters (heating elements) located inside the combustion chamber, well heads, to heat the fuel in order for it to ignite.
Should start and you can always repeat with maybe a few seconds more heat time.

Naturally I assume you follow all the other safety precautions.
Also use a heavy jumper (12 gauge) as plugs draw considerable current.

Another possibility is that the contacts inside the key switch are not making proper contacts which is fairly commonplace.
One cure for the switch is spraying WD40 into the key slot to free up dry lubricant that prevents proper contacting. That is if the switch is the culprit.
Otherwise it might be the glow plug relay module.

 

[booboo04]

Thanks MikePA, sounds like under the fender we go! I had just finished reading the same thing. I saw two switches under there, one with two black wires running into it on the side of the transmission (if I remember correctly) and another one that looked like it was dipped in plastic. Right spot?

 

[booboo04]

Piloon, we'll give that a try! Bypassing the glow plug timer going from the hot side of the battery to the glow plug interconnect. Got it. Thanks for the fresh ideas...you know how it can be chasing an electrical problem. Of course we will be very safety conscious!

 

[MikePA]

Thanks MikePA, sounds like under the fender we go! I had just finished reading the same thing. I saw two switches under there, one with two black wires running into it on the side of the transmission (if I remember correctly) and another one that looked like it was dipped in plastic. Right spot?

Yep, sounds like the right spot.

 

[2458n]

On the old chevy diesel trucks,the glow plug timer was just replaced with a heavy switch that passed battery current to the glow plugs for a count of 10. Start as usual.

 

[navistar505]

Sounds like a safety switch problem. As far as the glow plug problem goes its probably one problem causing everything. You do not need glow plugs to start the engine so I would figure out the starting issue first

 

[PILOON]

On the old chevy diesel trucks,the glow plug timer was just replaced with a heavy switch that passed battery current to the glow plugs for a count of 10. Start as usual.

YEP, done that also, in fact that is where I come from with my suggestion.
The price of the GMC (Chevy) timer is why I came up with plan B.
Knew one guy that simply clasped two wires between 2 fingers to glow his plugs.

Finding a HD switch capable of the current draw is difficult but an ATV starter relay or horn relay would do the trick.
__________________________________________________________________________________________________-
For safety switch (temporary for test) bypass simply short the 2 switch leads. ( or on some that use 1 female and 1 male connector just plug the F into the M.)

 

[torchroadster]

THEN: couldn't get the glow plugs to heat - no 12v to them. Replaced the ignition switch.
Also found problem with the plug that connects the ignition switch into the harness, so we bypassed that. Juice going through switch to the glow plug relay (12v). But from the relay to the glow plugs we only get 1.5 to 2v. Replace the timer relay. Still NOTHING...

Now we are really stumped. At one point, we got a click out of the third of the three like relays (which the parts diagram says is the PTO safety relay). We've swapped the relays around since they are all the same, and even carefully tried the new relay in each of the three positions. No joy. Wearing out the old wiring diagram.

ANY help, will dance at your next party!

The glow plug circuit is marked in yellow, the glow plug timer circuit is in blue and the circuit to the indicator lamp is in yellow.

The glow plug timer ONLY controls the glow plug indicator light on the dash board and the glow plugs are hard wired to the glow plug connection on the ignition switch. So the glow plug light not being illuminated does not mean the glow plugs are not working and replacing the timer will not affect the glow plug operation.

 

[keony]

View attachment 408560

The glow plug circuit is marked in yellow, the glow plug timer circuit is in blue and the circuit to the indicator lamp is in yellow.

The glow plug timer ONLY controls the glow plug indicator light on the dash board and the glow plugs are hard wired to the glow plug connection on the ignition switch. So the glow plug light not being illuminated does not mean the glow plugs are not working and replacing the timer will not affect the glow plug operation.

Well, I hope I don't muddy the waters, but my manual for TC29DA shows 3 relays: #3 = Glow plug power relay, #7 = Glow plug timer relay, and #6 = Glow plug lamp relay.
My diagram looks totally different than your post. Maybe the DA are totally different from the D models?